Fix Nginx Upstream Connection Refused Socket Error
When Nginx returns a 502 Bad Gateway or logs upstream connection refused
Checklists for software errors, setup, and tool workflows.
1. Reproduce
2. Isolate
3. Apply
4. Verify
Latest checklists
View listDocker Compose .env File Not Loading: Common Fixes
You set environment variables in a .env file next to your docker-compose.yml
Docker Desktop Engine Stopped on Mac M1: Fixes That Work
On Apple Silicon Macs (M1, M2, M3), Docker Desktop sometimes shows the error “Docker Desktop engi...
Node.js Heap Out of Memory in Production: Practical Fixes
You're running a Node.js application in production when it crashes with FATAL ERROR: In...
How to Fix Docker Image Pull Access Denied Error
When you run docker pull and see access denied, Docker cannot authentic...
How to Fix Node.js Heap Out of Memory Error Code 134
You're running a Node.js application and it crashes with FATAL ERROR: CALL_AND_RETRY_LA...
Topic paths
Quick titles
Fix pnpm ERR! Cannot Find Module – Practical StepsHow to Restart Windows Search Indexing ServiceRemote Desktop Can't Connect to This Computer: TroubleshootingResolve Python UnicodeDecodeError When Reading FilesHow to Resolve npm Install Permission Denied on LinuxHow to Resolve Port Already in Use in Docker ComposeTroubleshooting Nginx Upstream Connection Refused Port 80RDP Connection Failed Due to Firewall – Fix